Trying to Avoid a Cold? Skip the Vitamin D Supplements

And the hunt for the cure to the common cold continues

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Zinc, vitamin C, vitamin D, old-fashioned chicken soup. Chances are you’ve probably tried all of these remedies to ward off symptoms of a cold, but scientists now say that you can cross at least one of them off your list.

In the most rigorous study to date investigating whether vitamin D can protect against colds, researchers found that healthy adults who took large doses of the supplement were no less likely to come down with upper respiratory infections — including colds, flu and sinus infections — than those taking placebo.

The new study, led by Dr. David Murdoch and his colleagues at the University of Otago in New Zealand, followed 322 healthy participants who were randomly assigned to take either vitamin D or a placebo on a monthly basis for 18 months. All participants came to the research facility so that scientists could observe them taking the pills, but neither the volunteers nor the scientists knew which pills contained the vitamin and which were placebo. Those getting vitamin D supplements received 200,000 IU for each of the first two months, and then 100,000 IU monthly for the remainder of the trial. That amounts to more than 3,000 IU a day, when health officials currently recommend that most adults get about 600 IU of vitamin D daily (primarily to maintain bone health and avoid the bone-weakening disease of osteoporosis).

By the end of the study, participants in the vitamin D group had developed a cold or flu an average 3.7 times, compared with 3.8 times in the placebo group. Taking vitamin D also had no impact on the severity or duration of people’s symptoms nor did it reduce the number of workdays they missed.

(MORE: Megadoses of Vitamin D Offer No Benefit)

Scientists started looking at vitamin D for cold prevention after early studies showed that tuberculosis patients who had genes that efficiently metabolized vitamin D were less prone to serious lung infections. There was also the intriguing observation that people who lived in sunnier climates — and therefore presumably had higher levels of vitamin D, since the skin makes the vitamin when exposed to sunlight — also tended to have fewer colds than those who lived in areas with less exposure to the sun.

Previous clinical trials have led to similarly disappointing results, however. But the authors of the current study note that people who are deficient in vitamin D, which is thought to contribute to immune function, may yet benefit from taking supplements. Studies involving children in Mongolia, for example, where the harsh climate prevents much sun exposure, showed that vitamin D supplements helped lower respiratory infections by 50%.

As for the protective effect of extra vitamin D in healthy adults who already have normal levels: “Whether vitamin D can prevent colds is pretty much done and dusted in healthy people,” says Murdoch. “Now we need to focus on other groups.”

(MORE: Vitamins and Supplements Linked to Higher Risk of Death)

 

Recent studies also show the supplement may not be as helpful as hoped in preventing other diseases. For example, rigorous trials suggest that taking vitamin D in low-dose supplements (400 IU) doesn’t help healthy postmenopausal women avoid bone fractures — but higher doses may still be helpful, and the supplements do help prevent bone breaks in women living in nursing homes or assisted-living facilities. Also, taking vitamin D does not lower the risk of developing breast cancer.

That’s not to say that maintaining vitamin D levels isn’t necessary for good health overall: the vitamin is needed for the body to soak up bone-building calcium from foods. Good dietary sources of D include dairy products such as yogurt, eggs, cheese and fortified milk. Getting at least a few minutes of sunlight a day is also enough for the body to make adequate vitamin D, though experts note that increased public health warnings about the risk of skin cancer from sun exposure may be leading to more cases of D deficiency than doctors think.

Whether or not such people may benefit from taking supplements during cold and flu season, Murdoch’s latest findings suggest that for the majority of healthy individuals, chicken soup may have to do for now.

 

The new study was published in the Journal of the American Medical Association.

MORE: Is Vitaminwater Really a Health Drink?

Alice Park is a writer at TIME. Find her on Twitter at @aliceparkny. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.

33 comments
PeterPaulMichaelDirr
PeterPaulMichaelDirr

First thing first. In the winter months you get little to no vitamin d from the sun, as uvb rays don't penetrate the atmosphere. One way to know if your getting vitamin d from the sun is if your shadow is shorter than you are high. If the shadow is right under you than you are being blasted with uvb and will make lots of vitamin d. Secondly, cold weather doesn't give you influenza. So what does? It's coming in contact with the virus and I'd you have poor vitamin d levels you will get sick. Why haven't these scientists made a link between poor vitamin d levels (winter time) and getting the flu, as opposed to good vitamin d levels (summertime) and not getting the flu??? Try for yourself people. One month from your next winter take at least 5000 iu's of vitamin d a day and I bet you will avoid it as I do!

lovecookie
lovecookie

What a load of baloney!  Vitamin D is a natural preventative and cure for colds and flu.  Ever notice why you rarely see people with the cold or flu in the summer?  Because natural Vitamin D gets created by exposing the body sunshine.  Why don't you hear more about this? Because the pharmaceutical industry can't make money off this cheap vitamin, it's far more lucrative to pander flu shots.

CBX
CBX

Didn't a very old study in the 1950s already show that taking just vitamin D doesn't have any effect against the common cold? However, when taken together with vitamin A, it did have a positive effect. And I thought these days vitamin K2 is prefered over A for taking together with D3, since you can overdose A. So they should repeat this study (1) in a country that lacks sun, (2) with people that have very low vitamin D3 levels, and (3) combined with K2 and/or A. Otherwise this study doesn't show anything new, and was a waste of money no?

nysalesman
nysalesman

You didn't tell the rest of the story. While the monthly megadose group of the study got approx the same number of colds and flu as the control group, the groups given daily and weekly vitamin D had a significant decrease in colds and flu when compared to the control group. Time should be ashamed of itself for either 1) Misrepresenting the study for an attention getting headline, or 2) Being so lazy as to not ready the entire study or get your information 2nd hand, or 3) Being so scientifically ignorant that you misunderstood the study.

SinupretSa
SinupretSa

Interesting and very bold statement have been made here. Zinc, vitamin C, vitamin D are Vitamins that have been proven time after time, study after study, to work effectively with colds. The old-fashioned chicken soup many be a remedy that granny might have though of but at the end of the day it serves its purpose and that being keeping the body hydrated... after all they do say that you have to drink warm beverages when you have a sinus problem!

Robyn
Robyn

Magnesium activates Vitamin D - so if subjects are magnesium-deficient, you can take all the Vitamin D in the world and it won't be able to do it's job in the body.   These studies never account for the nutrient partnerships essential for health.

Elizabeth McCracken
Elizabeth McCracken

I see there is no distinction about what type of D. So, either the study, the article or both are bogus. 

goldengrain
goldengrain

Once I feel a cold coming on, I take an olive leaf extract capsule every morning.  It usually prevents it.  If I need more serious help, I take another, twelve hours apart.  No more than two per day.  Two doctors recommended this, one of whom was a Chinese acupuncturist.

I also tend to head colds and a stuffy nose at night and believe this to be partly allergies as this occurs this time of year.  I use a neti pot with salt and breathe freely all night. I awake well rested.  

I cannot recommend these remedies highly enough. Please try them. You will not be disappointed.

Mike Lowery
Mike Lowery

There's clearly a difference between monthly gigadosing and normal daily doses... Other previous studies have suggested exactly the opposite.  Why is this study being promoted as the definitive answer when it contradicts so much prior existing data?

http://www.lef.org/newsletter/...

allworld212
allworld212

I don't take vitamin D to prevent a cold.  I take it to help keep me healthy.  Besides,  the last time I checked, a cold is merely the bodies'  defenses having a fight with something trying to invade it. Sure it's uncomfortable, but I'm not sure I want to hinder my bodies' defenses, in any case.  If these rash of articles are supposed to make me stop taking vitamin D in lue of some pharma drug,  they've failed miserably.  I seen this time and again. Big industry bringing in hired guns to squelch something that may prevent them from making profit.

Ron Benefield
Ron Benefield

And the corporate empire continues its relentless attacks on natural health and healing as they sell their drugs in news articles and on TV. The corporate empire is spearheaded by the drug industry, the food industry, the oil industry and big banking, but by far the most dangerous is big pharma and Monsanto. Wake up- smell the coffee you are being put into corporate slavery.

dennisi
dennisi

did you know that vitamin D is best received via the sun? chemical vitamin D -vitamin D3 does not work - do not be fooled. do not use sunscreen either which contains pure chemicals (read the back) which harms your natural vitamin D absorption. do not be fooled. you must have your vitamin D daily but watch out because you can lose weight too fast.  ginger is the best natural medicine for colds. just peeling and slicing some up in a dish or in fresh fluoride free water for ginger tea works like MAGIC on colds.  xx den

Andy Jackson
Andy Jackson

Something is funny about that study.  Multitudes of other studies confirm Vit. D's efficacy in protecting people from colds, etc.  Somebody doesn't want us to be well.

savagenation
savagenation

322 people in a Medical study, really? That's not a Study, that wouldn't even qualify for a Shopping Mall Market Research Taste Test Survey

More BS from Big Pharma. Did they use syntheto garbage "prescription" or cheap drug store OTC vitamins like the last faux study. 

Don't listen to the Drug, Cut, Burn, amp; Poison Sick Care industry.

These are "geniuses" who riot over second hand smoke and lead paint flakes, but will inject your children with Mercury, and use it in dental fillings, saying it's "safe"..

 They make money on you dying...slowly.

Reythia
Reythia

Shocking.  Plenty of readers here who don't really CARE whether vitamin D is demonstrated to actually reduce colds, because their own personal experience "proves" that it does.  This despite the fact that they have a sample size of one -- themselves -- and no control case -- someone doing the same things they are, but not taking vitamin D.

Folks, no one is claiming vitamin D is bad for you, so if you want to keep taking it, go for it.  It'll do no harm.  But you've got ZERO evidence that it actually helps, either.  So it makes sense for healthy people who don't have the money to pony up for vitamin D pills to instead spend some time in the sun instead and make their requisite amount of vitamin D the natural way.  That's really all the article is saying.  Settle down.

David Flory
David Flory

A study with only 322 people is not a statistically significant.  You to have at least 10,000 in the study to have any strong evidence that Vitamin D is ineffective.  This is just more bad science.

CLS88
CLS88

I have not had even one cold or flu infection in the 7 years I've been maintaining my vitamin D health.

I have a blood level of 60 ng/ml.

Tim Goyetche Hom.MD
Tim Goyetche Hom.MD

I take 20,000 IU per day to maintain a healthy level in my body.    3000iu of Vitamin D might help a toddler but not an adult.

This study is like saying beer will not get you drunk because they had a bunch of people drink a shot glass full of beer and they did not get drunk.

Another study paid for by Big Pharma is my best guess.

bibleverse1
bibleverse1

Anything that puts the mind at ease wards off disease.

Linda Ponzini
Linda Ponzini

"Also, taking vitamin D does not lower the risk of developing breast cancer."

The link to Time's own story on vitamin D and breast cancer says no such thing.  Here's what the article actually said:  "Four hundred IUs is just not a lot," says Dr. Larry Norton, a breast-cancer specialist at Memorial Sloan-Kettering Cancer Center. "The supplementation wasn't adequate to raise blood levels enough in susceptible individuals to have a biological impact." 

And this:

"Experts wonder whether the trial lasted long enough to uncover any benefit on breast-cancer rates. Breast cancer typically develops over a long period, anywhere from five to 20 years, and researchers believe that vitamin D's effect on curbing cancer-cell growth may be most powerful in the disease's early stages."

Geez, you'd think the writer would at least read through her own links.

Steve Smith
Steve Smith

No amazing results on an average of >3,000 IU a day, and it's a done deal? Yet, though undetermined, higher-than-400-IU doses might still help in other cases?

What about 5,000 IU a day? What about daily supplementation vs. megadoses? Time of day taken, with what food? What about data on the patients' Vitamin D blood levels, and which of the two Vitamin D tests they used?

What of this unquestioned echo about fortified milk being a "good dietary source"? 100IU per cup? And all that sugar/carbohydrates and possible allergy? Say eggs are a good source (about 20IU per large egg), but sometime, somewhere else this same kind of news report will wage a war on whether you might dare eat even one egg for "fear of cholesterol" while saying nothing about the known nutritional differences in eggs based on chickens' diets.

This type of article does nothing to inform consumers on what choices they might make, let alone why. It is a summary and echo of one viewpoint.

It is imperative to separate the news reports on new findings in specific experiments from basic nutrition principles that are so often misunderstood by the authors of the news report. Even though there is no one Truth in nutrition, and though there are many conflicting views, studies, and camps, there is still a way to objectively write about these principles. 

If you want to write a news report on Vitamin D, look into the history of its recommended daily allowance. Try to find where they came up with the current number of IU -- others have already written about this, but it's still a fascinating story of how public policy (and to some extent, national health) can be shaped by anecdote.

It wouldn't hurt, either, to consider that there are alternative views on Vitamin D levels, sunlight exposure, and dietary sources. By all means, you don't have to endorse them or give them equal weight as the results of these trending studies, but it'd be right to find out about them. It's a problem that not every approach toward a given topic has the purse for its own study, and yet there are cheaper, though less publicized means of testing a hypothesis and generating a qualified conclusion, capable of at least helping us to keep an open mind and explore other possibilities.

Darian L. Smith
Darian L. Smith

"That’s not to say that maintaining vitamin D levels isn’t necessary for good health overall: the vitamin is needed for the body to soak up bone-building calcium from foods"           Then don't use the irresponsible title "Skip the Vitamn D Supplements".

Heather DeVaughn
Heather DeVaughn

I take 5,000 IU of vitamin D a day and it is barely enough to keep my blood levels in what is considered the normal range.  Most experts recommend 8,0000 IU for the prevention of disease.  My question in regard to this study is whether blood levels were monitored to see whether or not the 3,000 IU's administered were enough to prevent deficiency in the subjects?  If not, what does this study prove?

HONKYSAUCE
HONKYSAUCE

@lovecookie In warmer months/seasons of the year, viruses are not as infectious as they are in colder temperatures. It has absolutely nothing to do with sunlight, but rather the weather.

pc1397
pc1397

New age gibberish-- Vitamin D3 (aka cholecalciferol) is the form naturally produced by the body as a result of sun exposure, and it is chemically indistinct from exogenous cholecalciferol. I am not aware of a single reputable study that demonstrated any difference between sunshine-y cholecalciferol and pill-y cholecalciferol in raising serum levels. Do you have any scientifically-sound references to support your assertion that "chemical" vitamin D3 doesn't work? (by the way, ALL D3 is chemical D3- I think you mean exogenous D3, which again, is exactly the same thing, regardless of source). 

Wolf_Blitza
Wolf_Blitza

@savagenation, first, the vitamin D supplements and placebo were both provided by Tishcon Corp, which manufactures, patents, and markets supplements, not prescription pharmaceuticals.  So I don't see how this is "BS from Big Pharma"

Second, the level of vitamin D in the supplemented participants' blood was significantly higher than in the placebo group. So, the vitamin D supplements were legit.

Third, the data collection was blinded, and the vitamin D and placebo groups were randomized and compared with the standard 95% confidence interval and the p-values are listed in the study. In other words, sample size was taken into account in the statistical analysis, and the trial was large enough to find that there was no significant advantage of Vitamin D over a placebo. 

So if you can't tell the difference between a Double-blind Radomized Control Trial and a Taste-test Survey, then it would be helpful for you brush up on Critical Appraisal before giving your opinion.

pc1397
pc1397

er... if by "Big Pharma" you mean those that profit from the manufacture of pharmaceuticals, wouldn't they want you to believe that the use of their products do in fact help prevent a cold, respiratory infection, etc. etc.?  If this is BS, it isn't coming from them.

Maybe the chicken soup industry?

JustinTime314
JustinTime314

Same here. Since I started taking at least 1000IU of D3 per day, I haven't had a cold or flu in over 3 years (no flu shots either).

I used to get sick at least twice a year, especially when traveling. I was even starting to get bronchial infections every year, even in the spring until I started taking D3.

Now I do still get infected on occasion, but my immune system knocks it out in 24 hours. The only symptoms are a slight headache and maybe a mild fever. No major cold or flu symptoms. No runny nose, sore throat, cough, aches or chills.

I ignore these kinds of studies, when my body tells me otherwise.

Taurus Londoño
Taurus Londoño

"20,000 IU per day to maintain a healthy level in my body"Dr. Goyetche, that's an amount vastly in excess of the upper intake level advised by the IOM; it's also in line with the toxicity threshold associated with *increased* risk of negative outcomes.

Indeed, not even the pro-Vitamin D lobby groups like the Vitamin D Council advises such an intake.

What *exactly* is a "healthy level" for you?

Reythia
Reythia

 Then I have some snake oil I can sell you.

pc1397
pc1397

I think (hope) you meant 8,000 units; 80,000 units strikes me as a tad high.

Seth Kaplan
Seth Kaplan

People living in parts of the country/world which do not receive consistent amounts of sunlight--think Anchorage versus Aruba--need to supplement their D3 levels. Most folks should aim for a D3 level of 70 or more. As some above have noted, it can take a 6 months to a year for someone with low D3 levels to supplement enough--say 50,000 IU once/week--to get a consistently healthy level. For those people, supplementation isn't a choice, it's a necessity.